Metal ion modified high surface area materials for odor removal and control

Abstract

This invention relates to modified high surface area materials, such as nanoparticles that are coated with metal ions, and articles treated with the modified high surface area materials. The modified nanoparticles have active sites that bind various gases and/or odorous compounds, thereby removing these compounds from a medium such as air or water. Metal ions are adsorbed onto the surface of the nanoparticle and bound strongly to the surface. By selection of the metal ion, specific gaseous compounds and/or odorous compounds can be targeted and removed efficiently and effectively from both aqueous phase and from the air. The modified nanoparticles are applied to nonwoven webs to provide odor removing articles for industrial and consumer use in refrigerators and trash containers.

1. An odor absorbing article of manufacture, comprising:
 a nonwoven web treated with a nanoparticle, the nanoparticle including silica, alumina, or combinations thereof and wherein the nanoparticle includes about 20-200 metal ions adsorbed onto the nanoparticle, wherein the adsorbed metal ions include copper ion, iron ion or combinations thereof and are active sites on a surface of the nanoparticle for binding gaseous or odorous compounds to the nanoparticle surface removing the compound from a surrounding environment. 
 
     
     
       2. The article of  claim 1 , wherein the odorous compound comprises a compound selected from the group consisting of sulfur containing compounds, nitrogen containing compounds, oxygen containing compounds, and combinations thereof. 
     
     
       3. The article of  claim 1 , wherein the substrate comprises a gas permeable material. 
     
     
       4. The article of  claim 1 , additionally comprising an adhesive material on one side of the substrate. 
     
     
       5. The article of  claim 4 , additionally comprising a removable layer disposed over the adhesive material on a side opposite the substrate. 
     
     
       6. The article of  claim 1 , further comprising a plurality of substrate pieces, the plurality of substrate pieces having an average piece outer surface area of about 1 cm 2  or less. 
     
     
       7. The article of  claim 1 , further comprising a plurality of substrate pieces, the plurality of substrate pieces having an average piece outer surface are of about 0.5 cm 2  or less. 
     
     
       8. The article of  claim 1 , wherein the nanoparticle comprises a surface area of at least about 200 square meters/gram. 
     
     
       9. The article of  claim 1 , wherein the article comprises a wipe. 
     
     
       10. An odor absorbing article of manufacture, comprising:
 a nonwoven web; and 
 a plurality of modified nanoparticles on the nonwoven web, each of the plurality of modified nanoparticles including about 20-200 metal ions adsorbed per nanoparticle, the nanoparticle including silica, alumina, or combinations thereof, wherein each of the adsorbed metal ions is capable of binding at least one gaseous compound or odorous compound to the modified nanoparticle removing the compound from a surrounding environment. 
 
     
     
       11. The article of  claim 10 , wherein the plurality of metal ions comprises copper ions, iron ions, or combinations thereof. 
     
     
       12. The article of  claim 10 , additionally comprising an adhesive material on one side of the nonwoven web. 
     
     
       13. The article of  claim 10 , further comprising a plurality of nonwoven web pieces, the plurality of nonwoven web pieces having an average area of about 1 cm 2  or less. 
     
     
       14. An odor absorbing article of manufacture, comprising:
 a nonwoven web; and 
 a plurality of modified silica nanoparticles on the nonwoven web, each of the plurality of modified silica nanoparticles including about 20-200 copper ions adsorbed per nanoparticle wherein each of the adsorbed copper ions is an active site on a surface of the silica nanoparticle for binding a gaseous or odorous compound to the silica nanoparticle surface removing the compound from a surrounding environment. 
 
     
     
       15. The article of  claim 14 , additionally comprising an adhesive material on one side of the nonwoven web. 
     
     
       16. The article of  claim 14 , further comprising a plurality of nonwoven web pieces, the plurality of nonwoven web pieces having an average piece outer surface area of about 1 cm 2  or less. 
     
     
       17. The article of  claim 1 , wherein the nanoparticle comprises a first Zeta Potential of about −1 to −50 millivolts and a second Zeta Potential after adsorption of the metal ions, the second Zeta Potential being higher than the first Zeta Potential as measured in a solution or suspension. 
     
     
       18. The article of  claim 1 , wherein the nanoparticle comprises a first Zeta Potential of about 1 to 70 millivolts and a second Zeta Potential after adsorption of the metal ions, the second Zeta Potential being lower than the first Zeta Potential as measured in a solution or suspension. 
     
     
       19. The article of  claim 17 , wherein the second Zeta Potential is at least about 5.0 millivolts higher than the first Zeta Potential as measured in a solution or suspension. 
     
     
       20. The article of  claim 18 , wherein the second Zeta Potential is at least about 5.0 millivolts lower than the first Zeta Potential as measured in a solution or suspension. 
     
     
       21. The article of  claim 14 , wherein the modified silica nanoparticles comprise a first Zeta Potential of about −1 to −50 millivolts and a second Zeta Potential after adsorption of the copper ions, the second Zeta Potential being higher than the first Zeta Potential as measured in a solution or suspension. 
     
     
       22. The article of  claim 21 , wherein the second Zeta Potential is at least about 5.0 millivolts higher than the first Zeta Potential as measured in a solution or suspension. 
     
     
       23. The article of  claim 14 , wherein the modified nanoparticles are coated on the nonwoven web in an amount of about 0.001 to 10.0 grams per square meter.